Fuel manifolds for gas turbine engines may be assembled from a sequence of manifold adaptors and transfer tubes. The manifold adaptors support nozzles for injection of fuel in the combustor. Transfer tubes interconnect manifold adaptors, and form primary and secondary fuel-supply networks therewith, to supply the nozzles with fuel. There is a risk of fuel leak at the connection between transfer tubes and the manifold adaptors. Accordingly, there is a need to provide an improved fuel manifold configuration.